Method and apparatus for making refractory bricks



Nov. 28, 1933. E. LUX El AL 1,937,023

METHOD AND APPARATUS FOR MAKING REFRACTORY BRICKS Filed April 17, 1931 2 Sheets-Sheet l nveniars A m M ff- Y Nov. 28, 1933. E. LUX El AL METHOD AND APPARATUS FOR MAKING REFRACTORY BRICKS ZSheetS-Sheet 2 Filed April 17,' 1951 I I p.

72200250715: X434 M M;

Patented Nov. 28,1933 1,937,028

METHOD AND APPARATUS FOR MAKING REFRACTORY BRICKS Elisabeth Lux, Essen, and Wilhelm Heinrich Daniels and Eberhard Kiihn, Dusseldorf-Heerdt, Germany, assignors, by mesne assignments, to The Koppers Company of Delaware, Pittsburgh, Pa., a corporation of Delaware Application April 17, 1931, Serial No. 530,874, and

in Germany April 16, 1930 Claims. (01. 25-41) The present invention relates to the manufacit is especially suitable for making large bricks ture of "shapes for making refractory bricks, these of very irregular external form. shapes being made from masses or compositions Another object of the invention is a method which consist of non-plastic, refractory and of making compressed shapes for the manufac- 5 granularmaterials, such as baked clay, quartz, ture of refractory bricks, wherein the molding a0 corundum, sillimanite, silicon carbide and the mass is covered by a plate which partially or like, or mixtures of these substancesbesides also entirely closes off the interior of the molding a little clay-but possibly none at alland liquebox and which is set into vibration, whilst at fying agents, such as humic acid, alkalis or the the same time the molding box itself is set into like, the whole being worked together with water. vibration by more than 2000 percussive blows 65 In the manufacture of compressed shapes for per minute. Q making refractory bricks, the usual process of Further objects of the invention are concerned compressing the loose mass has been to ram or with devices for carrying out the processes above stamp it in a mould. By using this method howset forth.

l5 ever, it has not been possible to carry out the The invention will now be explained in con- 70 compressing of the shapes beyond a certain dejunction with th accomp nyin drawing Whi h gree, so that the shapes were comparatively show practical examples for carrying out the porous and their density at various places of the process. The invention is not limited to these shape was not uniform, specific embodiments however.

The present invention now relates to improve- Figure 1 gives a side elevation, pa in 7 ments in the manufacture of shapes for protion, of a machine for carrying outthe process. ducing refractory bricks from the above molded Fig. 2 is a sideelevational View. Partly in os masses. section, illustrating another embodiment of the A primary object of the invention is a method invention for the manufacture of small shaped of making compressed shapes from the said bricks in accordance with the method of. the

masses, wherein a molding box giving form to the present invention. bottom and sides of the shape, is filled with In the arrangement shown, the molding mass a weighed quantity of the above mixture worked 15 is received by a molding box 14, which is up with water, then a weighted plate entirely or secured to the table 10 of an ordinary shakpartially closing the mold, is placed on the top ing machine 11 by means of screw clamps 1, 85 of the mass in the molding box whereupon this which ip t reinforcing rib 2 0f the o dplate/is set into vibration by receiving more ing box. The sides of the preferably castthan '2000 percussive blows per minute without iron molding b e Covered i side with an the plate being lifted from the surface of the interchangeable lining Sheet 3 which is Prefermold, until the desired compressing or impacting ab1Y of steel and 15 to P c P the wccjring 90 of the mass is obtained. Due tothe action of the Inner walls of thefnoldmg S the vibrated n weighted plate, the molding table 10 of the machme 11 is provided as usual mass passes,provisionally into a doughy, plastic $32 28 fi ai g i gg ggz? gs gg s gi gg state m whlch the granular component's of theg pressed air which is led in through the pipe 12 mass are able to settle themselves very densely. and out throu 95 ghthe pipe 13. The shaking mat desn'ed degree. *t chine 11'is provided at the side with a bracket. 4 pression is reached, the vibration of the weighted carrying above the molding box a vertical guide plate. 15 decontmuecv-whereupon the massets 18 for a slide 5 to which is attached a device or stiffens in -a relatively short time, so that the 17, whereby t weighted plate 1 pushed t t 1 s ap may asily be r m ved from th molding hollow interior of the molding box 14 and closing box without therisk of damage. on th top of the mass, may be set into vibration A further object of the invention is a method by more than 2000 percussjons per minute. The whereby the molding mass charged into the molddevice 17 is substantially the same as the usual 5 ing box is covered on to p with a loaded and vipneumatic hammer- I comprises a Piston 6/ brated plate, whilst at the same time the molding which by means of compressedair ledin through box is placed upon a shaking table of usual type Ji p pe 19 n Out h h 'p pe 20. is 01 which vibrates with less than 2000 oscillations atcd in Such a Way that it strikes a die 01 Stamp per minute. During this process, a particularly 7 more than 2000 times D u his i intense impac'tingof the mass takes place and 7 is movablyfltted into the bottom opening of 11 control lever 21 is provided with an extension 9,"

to which a tension spring 22 attached to the slide 5 is secured, this spring serving to keep the hand lever 21 at the closed position when in the unloaded condition.

Vertical movement of the slide 5 and therefore of the vibration device 1'7 is imparted by a double lever 23, which is pivotally mounted in a bearing 24 of the bracket 4. At 25, through themedium of a resilient intermediate member 26, the double lever 23 is hingedly connected to a cam 27 of the slide 5 in such a way that when the double lever 23 is swung up and down, the slide 5 is taken along on the guide 18 at the same time. Finally, the double lever 23 is furnshed at one end with a handle 28 and at the other end with a balance weight 29.

Instead of the vibration device being vertically controlled by a hand lever, it is of course also possible for it to *be moved up and down by a vertical screw spindle or by a hydraulic device. In both'cases an elastic, sprung intermediate member must naturally be inserted between the driving means and the device 17. Further it is also possible for the vibrations to be imparted to the weight plate by several percussion pistons, which is of great advantage when large shapes are to be made.

When using the arrangement as shown in Figure 1 for carrying out the process according to the invention; the method is as follows: The wetted and mixed mass 15 is charged into the mold 14, the vibration device 17 being meanwhile in the top position. The weight plate 16 is now pushed into the hollow space of the mold 14 after first of all levelling out the mass in the mold. Now the vibration device is lowered by means of the double lever. 23 until the plunger 8 rests on theweight plate. Then the control lever 21 is actuated so that the striking piston comes into operation and the stamp or plunger 7 is set into vibration and the weight plate 16 along with it.

In the meantime thevibration device 17 is firmly borne down on the weight plate 16 by means of the double lever 23. device 17 is kept in action until the desired compressing of the mass 15 has been attained, this being preferably ascertained by the sinking of the weight plate 16 inside the molding box up to a mark applied to the inside of the mold. Then the vibration device 17 is brought to a standstill, the slide 5 raised to its top position so that the mold can now be taken apart for the removal of the shape.

In the arrangement shown,'if the molding box is also to be set into vibration at the same time, the compressed air is delivered to the inlet pipe of the shaking device 11 in such a quantity that the table 10 of the shaking machine travels through the required distance.

The arrangement shown in Figure 1 may also be used for bringing about the compression by setting the molding box into vibration. In this case however the piston of the shaking device is not connected to the shaking table 10 but is so arranged that, just like the vibration device .17, it strikes against the bottom of the table 10 in such rapid succession that the table 10 receives more than 2000 blows per minute.

The vibration According to the drawings in Figure 2, the forming mass 30 is placed in a molding box 31, which is capable of being taken apart, the sides being held together by means of wing nuts 32 and screwed spindles 32'. The molding box is secured to a table plate 33 which has a flat and level top. The mass in the mold is compressed by a plate 34, which has an upwardly extending shank 35, the top end of which passes into the guide sleeve 37of a device 38 after the nature of a pneumatic hammer. As usual, the device 38 is provided with a striking piston 39 which is driven. by means of compressed air flowing in through the pipe 40. In its bottom position, the piston 39 strikes the end of the shank 35 of the plate 34. The travel of the piston is so chosen that with a certain air pressure, it imparts more than 2000 beats per minute to the end of the shank 35.

Furthermore, the device 38 is provided at the top with a handle 41 on which is arranged a finger lever 42 for actuating a valve arranged inside the handle 41 and controlling the inlet vice shown in Fig. 2 is used for carrying out the process according to the invention, the molder grips the shank 35 of the vibrating plunger with one hand and the handle of the pneumatic hammer with the other one and places the bottom of the plate 34 on the top of the mass inside the mold 31. Then he opens the air valve 42 and goes backwards and forwards over the surface of the mass with the vibrating stamp until the mass has passedinto the desired doughy plastic state at all places and has acquired the required density. In order to obtain a fiat surface on the shape it is advisable towards the end of the compressing operation, to place a plate on top of the mass in the mold and to set it into vibration for a little longer using the device shown in Figure 2. When the shape is finished, the wing nuts of the mold are slackened off and the mold taken apart.

With the arrangement as shown in Fig. 2, the plate 34 is shown flat at the underside. In certain cases however, particularly when a shape is to be built up in several layers as is the case with complicated shapes, it is advisable to provide the bottom of the ram with grooves so as to ensure a goodunion of the layers with each other. It is alsopossible to make the bottom of the ram 34 slightly conical.

Ceramic shapes produced according to the invention are preferably made from compositions which contain but little clay, e. g. less than 10% or even no clay at all. It is' also of advantage to add defiocculating agents which facilitate the shaping of the mass. Below are given examples of masses free from and containing clay, which may be used to advantage in the process according to the present invention: 1

A. Mass free from clay.-500. kilograms of quartzite are ground in a wet pan-to a grain size of 5 mm., at the maximum 3% CaO in the form of milk of lime and 1% liquor from the sulphite process of cellulose manufacture being added. The water content of the mass should be about 7%.

B. Mass containing chm-200 kilograms of baked clay ground to a grain size of 4 mm. at the maximum are mixed in an open trough mixer with 20 kg. clay, 15 liters of water and'0.1% sodium carbonate. The mixture may be treated according to the method described.

It is to be distinctly understood that the above process is not limited to the specific details disclosed above and we claim as part of our invention all modifications which may reasonably fall within the scope of the appended claims.

' We claim:

1. A method of making compressed shapes of definite dimensions for the manufacture of reiraotory bricks from refractory and granular materials worked up with a liquid, the said materials being at least substantially free of clay, which method comprises depositing a weighed quantity of such a prepared mixture into a mold which defines the bottom and sides of the shape, placing a weighted plate on the top of the mass, setting this plate into vibration by more than 2000 percussions per minute and at the same time shaking the molding box in such a way that the lattermakes less than 2000 oscillations per minute, until the desired compressing of the mass is attained and maintaining the weighted plate firmly down on the surface of the mass and against retractive movement relative thereto during the vibration of said plate on the mass.

2. A device for molding mixtures and comprising a molding box open at the top, a weighted plate movable vertically for insertion inside the molding box, means for setting this plate into vibration by more than 2000 percussions per minute, said plate being arranged relative to said vibration means so as to prevent retractive movement of it relative to the mold during the operation of the vibration means for setting the plate into vibration, and means for setting the molding box into vibration by more than 2000 percussions per minute.

3. A device for molding mixtures and comprising a molding box open at the top, a weighted plate movable vertically for insertion inside the molding box, means for setting this plate into vibration by more than 2000 percussions per minute, said plate being arranged relative to said vibration means so as to prevent retractive movement of it relative to the mold during the operation of the vibration means for setting the plate into vibration, and means for setting the molding box into vibration by more than 2000 percussions per minute, the said weighted plate being smaller in cross-section than the crosssection of the top of the molding box.

4. A device for molding mixtures and comprisment of it relative to the mold during the operation of the vibration means for setting the plate into vibration, and means for shaking the molding box, a support for slidably supporting said vibration means, a lever pivotally mounted on said support and hingedly connected to a cam on the vibration means whereby to raise and lower said vibration means, said lever and cam being adapted to bear the, vibration means firmly down on the weight plate when lowered onto the mold.

5. A device for molding mixtures and comprising a molding box open at the top, a weighted plate movable vertically for insertion inside the molding box means for setting this plate into vibration by more than 2000 percussions per minute, said plate being arranged relative to said vibration means so as to prevent retractive movement of it relative to the mold during the operation of the vibration means for setting the plate into vibration, means for setting the molding box into vibration by more than 2000 percussions per minute, the said weighted plate be- -ing smaller in cross-section than the top opening of the molding box, a weighted plate greater in diameter the... the top opening of the molding box adapted to shape the upper surface of the shape after the mass is compressed, means for setting the said larger weighted plate into vibration by more than 2000 percussions per Ill) 

